Use singular array element variable name for no-fn-reference-in-iterator rule if possible

[fisker]

const foo = items.map(fn);

We are suggesting

const foo = items.map((element) => fn(element));

const foo = items.map((element, index) => fn(element, index));

const foo = items.map((element, index, array) => fn(element, index, array));

We can use better variable name

const foo = items.map((item) => fn(item));

const foo = items.map((item, index) => fn(item, index));

const foo = items.map((item, index, items) => fn(item, index, items));
//                                  ^^^^^ this is not related, but we can use this name